The Risk of Ischemic and Hemorrhagic Stroke in Patients With Idiopathic Inflammatory Myopathies: A Swedish Population‐Based Cohort Study

• Published in: Arthritis care & research (2010) 2019-07, Vol.71 (7), p.970-976
• Main Authors: Moshtaghi‐Svensson, John, Lundberg, Ingrid E., Von Euler, Mia, Arkema, Elizabeth V., Holmqvist, Marie
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Age; Age Factors; Aged; Aged, 80 and over; Brain Ischemia - diagnosis; Brain Ischemia - epidemiology; Cohort analysis; Death; Diagnosis; Emigration; Female; Hemorrhage; Humans; Incidence; Inflammation; Intracranial Hemorrhages - diagnosis; Intracranial Hemorrhages - epidemiology; Ischemia; Male; Medicin och hälsovetenskap; Middle Aged; Myositis - diagnosis; Myositis - epidemiology; Population; Population studies; Population-based studies; Prognosis; Prospective Studies; Registries; Risk Assessment; Risk Factors; Sex Factors; Stroke; Stroke - diagnosis; Stroke - epidemiology; Sweden - epidemiology; Time Factors; Young Adult
• ISSN: 2151-464X; 2151-4658; 2151-4658
• DOI: 10.1002/acr.23702

Objective To study the occurrence of ischemic stroke and hemorrhagic stroke in patients with idiopathic inflammatory myopathies (IIMs) compared to that in the general population and to investigate how it varies by sex, age, clinical subdiagnosis, and time since IIM diagnosis. Methods All patients in Sweden with newly diagnosed IIM were identified from the National Patient Register, and general population comparators were identified from the Total Population Register. The study population was followed prospectively until death, emigration, December 2013, or first incident stroke. Incidence rates, rate differences, and hazard ratios (HRs) comparing patients with IIMs to the general population were estimated and stratified by age, sex, type of IIM, and time since diagnosis. To account for the competing risk of death, the subdistribution HR was estimated using Fine and Gray models. Results We observed 34 and 229 stroke events in 663 IIM patients and 6,673 comparators, respectively. The HR was elevated for ischemic stroke (HR 2.1 [95% confidence interval (95% CI) 1.4, 3.0]). Few hemorrhagic stroke events were identified, but an increased risk was observed (HR 1.9 (95% CI 0.7, 5.5]). The association remained elevated for both outcomes when taking the competing risk of death into account. For ischemic stroke, the rate difference was highest in the oldest age group (≥68 years), while the HR was highest in the youngest age group (